Shuttle Atlantis Takes a Short Trip

The space shuttle Atlantis, the second orbiter slated to launch since the Columbia disaster, rolls out of its Orbiter Processing Facility at NASA's Kennedy Space Center on July 22, 2005. CREDIT: T. Malik.

CAPE CANAVERAL, Fla. - Despite two delay-filled days, the shuttle Atlantis is safely inside NASA's massive Vehicle Assembly Building (VAB) after a brief hop forward in its long road toward space.

Shuttle engineers rolled the Atlantis orbiter into the VAB, where it will be mated to its external tank-solid rocket booster launch stack for NASA's STS-121 mission, at about 10:20 a.m. EDT (1420 GMT) Friday.

Landing gear glitches plagued Atlantis' rollover from its Orbiter Processing Facility (OPF) to the VAB.

Initially slated to rollover in the morning hours of July 20, Atlantis did not start moving until about 9:41 a.m. EDT (1341 GMT) Friday, and five minutes later breached the outer doors of its OPF hangar.

On July 20, engineers found a faulty tire pressure sensor connection between Atlantis' front left tire and the orbiter, prompting engineers to change out the tire, which NASA officials said was an easier fix than repairing the connector itself. Additional problems retracting Atlantis landing gear, which must be tucked inside the orbiter during rollover operations, also delayed the event, NASA officials added.

"This is great," a NASA shuttle worker said as the orbiter rolled past photographers, reporters and excited NASA employees. "Especially after all this delay."

NASA has tapped Atlantis as its second shuttle to launch since the 2003 Columbia disaster. Its STS-121 mission, set to launch in September with astronaut Steven Lindsey in command, is the final test flight to shakedown new orbiter inspection tools and methods, as well as external tank modifications, before the space agency resumes major construction missions to complete the International Space Station (ISS).

The mission will follow the STS-114 spaceflight of Discovery, which is slated to launch at 10:39 a.m. EDT (1439 GMT) on July 26. Atlantis is expected to serve as a rescue ship for the STS-114 astronauts in the unlikely event that Discovery is severely damaged during flight and its crew forced to take refuge aboard the ISS.

"Everything you've done to Discovery, we've done to Atlantis too," Scott Thurston, Atlantis' vehicle manager, told SPACE.com before the rollover, adding that his crew had less time to perform the work since all new hardware and procedures went to Discovery first. "We've basically had less time, because everybody focused on getting those deliveries to Discovery...it's a big accomplishment."

The orbiter will hold updated cameras and sports a new, 50-foot (15-meter) boom tipped with cameras and laser sensors to probe vulnerable heat-resistant areas for damage during flight. During a spacewalk, an STS-121 astronaut will ride the end of the boom, which will be attached to the tip of Atlantis' robotic arm, to test its dynamics with such a load.

"We've got a special relationship with these vehicles that we see every day," Thurston said. "Everybody's got a different thing that they hold very dear." 

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